I always thought that the SIM card contains the MSISDN (Mobile Station ISDN number), i.e. full phone number of the phone. But on some searching on the net I found out that it may or may not. I'm a little confused about this & will really appreciate if some one knows this.
This is a very elementary question, but essentially what is the purpose of a detachable SIM & what does taking it out of one phone & putting in another achieve?
"A problem well stated is a problem half solved.” - Charles F. Kettering
SCJP 6, OCPJWCD
Joined: Aug 04, 2011
The SIM contains another number which is recognized by the Mobile Operator and then the SIM is given the phone number.
I am not 100% sure but I think you can change your number without changing the SIM, right ?
The two numbers always stored on the SIM card is the ICCID and IMSI, to identify the network and the user respectively. Other data is stored on the SIM, but the ICCID and IMSI are required for it to work.
The MSISDN is not always stored on the SIM Card and can be editted by a user with the correct know how.